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Palladium-catalyzed asymmetric [3 + 2] trimethylenemethane cycloaddition reactions.

ABSTRACT: Transition-metal-catalyzed trimethylenemethane (TMM) [3 + 2] cycloadditions provide direct routes to functionalized cyclopentanes. This reaction has been shown to be a highly chemo-, regio-, and diastereoselective process. We report a palladium-catalyzed asymmetric [3 + 2] trimethylenemethane (TMM) cycloaddition between 3-acetoxy-2-trimethylsilylmethyl-1-propene and various di- and trisubstituted olefins. Yields of exo-methylenecyclopentane products range from 59 to 99%, and enantiomeric excesses range from 58 to 92% ee.

SUBMITTER: Trost BM

PROVIDER: S-EPMC2535802 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Palladium-catalyzed asymmetric [3 + 2] trimethylenemethane cycloaddition reactions.

Trost Barry M BM Stambuli James P JP Silverman Steven M SM Schwörer Ulrike U

Journal of the American Chemical Society 20061001 41

Transition-metal-catalyzed trimethylenemethane (TMM) [3 + 2] cycloadditions provide direct routes to functionalized cyclopentanes. This reaction has been shown to be a highly chemo-, regio-, and diastereoselective process. We report a palladium-catalyzed asymmetric [3 + 2] trimethylenemethane (TMM) cycloaddition between 3-acetoxy-2-trimethylsilylmethyl-1-propene and various di- and trisubstituted olefins. Yields of exo-methylenecyclopentane products range from 59 to 99%, and enantiomeric excesse ...[more]

PMID: 17031924

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